Synthesis of Benzazepinones via Intramolecular Cyclization Involving Ketene Iminium Intermediates
Helvetica Chimica Acta, cilt.102, sa.9, 2019 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 102 Sayı: 9
- Basım Tarihi: 2019
- Doi Numarası: 10.1002/hlca.201900168
- Dergi Adı: Helvetica Chimica Acta
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Anahtar Kelimeler: benzazepinone, cyclization, cyclobutanone, keteniminium
- Boğaziçi Üniversitesi Adresli: Evet
Özet
Herein, we describe a very straightforward and metal free method for the synthesis of benzazepinones through an intramolecular cyclization. This involves an ortho-vinyl-anilino-amide as starting material which is converted to a keteniminium intermediate that spontaneously cyclize to form a 7-membered ring iminium. Under slightly basic hydrolysis conditions, this latter is ultimately converted to the desired benzazepinone. Control experiments on the electron density of the nitrogen constituting the aniline were performed to support our proposed mechanism and rationalize the selectivity of the reaction.